Leak down test on 550

I recently had a complete service done on my '99 550 maranello. It included the timing belts (at 24,100 miles), and a leak down test was performed as well at my request. I do understand the concept that the gauge shows the loss percentage which indicates the condition of the cylinder and overall condition of the engine. The less the “loss” percentage the better the condition the engine is in.

Based on the individual readings I got, I have the following questions:

1) In general, the findings show a loss percentage below 10% which indicates that my engine is in great to good running condition.
--> Is that a correct statement ?

2) In particular, there appear to be great variances between the single readings.
- cyl. # 1, 2, 3, 6, 8:____9%
- cyl. # 4:____________7%
- cyl. # 5, 9:__________4%
- cyl. # 7:____________5%
- cyl. # 10, 11:________11%
- cyl. # 12:____________8%
There is a great inconsistency (high to low) in leakage of 63% between cylinders 10, 11 and cylinders 5 and 9.
--> Anything to be concerned about ?

3) Let’s assume that the above variances are of no consequence, it looks like cyl # 10 and 11 (both over 10%) are going to create a problem sooner than later.
--> Is that a fair assumption ?

4) Based on the above, would anyone be able to give me an opinion as to the condition of my engine (i.e. rings, valves, and head gasket) ?

Thanks.

 

At this time i would not worry about it. The readings are a controversial snap shot in time of a dynamic system. It is like your arm hurts and the doc only takes 1 xray. He has got some data but it must be used in context with the rest of an exam before a conclusion can be drawn. More digging needs to be done before anything meaningful can be said. Drive the car and enjoy it. The numbers are not great but do not warrant more intervention. The 550 is not the 355 with known valve guide issues.

 

think you should probably looks to sell it asap

 

lol

 

Wanna buy ???

 

i will buy anything at the right price......

post up the info or pm me

 

Not selling. Just trying to get some tech info ;-)

 

Willy, done hot or performed cold? Makes a big difference on the readings. You want hot.

Did the mechanic who performed the test indicate if it was leaking through the valves or past the rings?
Philip

 

Performed @ cold. No word on "leakage" as it passed without comments.

Wanna get really technical ?
Does the following comparison entice you to a comment?

--> Leak Down (comparison @ cold) <--

March 2015..................November 2011
@24,158 miles.............@13,063 miles

- cyl. # 1:____9%.........10%
- cyl. # 2:____9%.........10%
- cyl. # 3:____9%.........10%
- cyl. # 4:____8%.........10%
- cyl. # 5:____4%.........6%
- cyl. # 6:____9%.........7%
- cyl. # 7:____5%.........5%
- cyl. # 8:____9%.........4%
- cyl. # 9:____4%.........11%
- cyl. # 10:__11%.........12%
- cyl. # 11:__11%.........10%
- cyl. # 12: ___8%.........11%

 

My comment stands. You just proved it. You got 4years 10,000 miles of enjoyment and little variation. Keep driving it.

 

Thank you for your time and your encouraging words. I will (I do) enjoy every driving moment.